i s p e t t i t s m i t h



UNTE

FRANCIS PETTIT SMITH,

OF LONDON, ENGLAND.

PROPELLING STEAM AND OTHER 'VESSl-lii.

Specification of Letters Patent No. 2,353, dated November 12, 1841.

1o @ZZ fro/1.0mz't may concern le it known that l, Francis Pe'r'rrr Sirrni, a subject ot the Queen ot Great Britain, and now residing at No. l lVades Terrace, East'lndia Road, in the county oit Middlesex, in the said Kingdom ot Great Britain, gentleman, have invented or discovered new and useful Manner ot Arranging and Combining the Propellino Apparatus for Steam and other Vessels; and l, the said Finnois Pirr'ri'r SiirrH, do hereby declare the nature ot my invention, and 'the manner in which the same is to be performed are fully described and ascertained in and by the following statement and description thereof, reference being had to the drawing hereunto annexed, and to the figures and letters marked thereonwthat is to say, my invention consists ot a sort ot screw or worin made to revolve rapidly under water in a recess or open space termed in that part of the after part ot the vessel commonly called the dead rising or dead wood 7 t the run.

Bescription or" the drawing, that is to say, Figure l, is side view ot a boat, or vessel, to which my said invention is appli-ed. It, is a broad-threaded, revolving screw or worm. B, is the shaft around which ththread, or worm, is fixed. BX, is a continuation et the shaft which connects the propeller with the steam engine, or other moving power, and gives motion to the screw, or worin; which screw, or worin placed and ranged as here shown is in tact the improved propeller. C, C, are two plunnner blocks, er bea-rings, which carry or support the snatt B, and the propeller. l), D, D, is a strong wrought-iron knee on which the plummer blocks C, C, .are firmly r'lXed and which ties the two perpendicular sternposts E, E, to the keel. E, E, are the two perpendicular sternposts which are rabbeted to the keel and to which are attached the tore and after hulk-heads forming two sides oit the well through which the propeller may be got at when it is wished to unship, or repair, the same. F, is the opening, or space, in the dead wood, or run, oit the vessel. G, is the stern post-H, the keel-l, is a stutting box through which the shaft B, is continued to the engine, or other moving power, giving motion to the screw, or worm-J, UT, is the water line-K, l, is the dead wood ot the vessel.

Fig. Q, is the end, or stern, view of the vessel, taken at the section ot' the foremost bulk head, and A, is the end view ot the propeller, or screw. G, is the sternpost. il, the keel of the vessel, It should be stated that it is not absolutely necessary that the thread ot the screw should make a complete turn around its axis, it may be less than a complete turn around the axis, it desired.

Fig. 3, shows another arrangement of screw, for the purpose ot propelling vessels, the same letters oit reference being used to indicate similar parts as are employed in the former igures; but in the present instance in place ot the screw A, having but one thread, or ,vorm, the screw ft, at Fig. 3, has two threads; and this, consequently, tor the same power, will require only one-halt the room, or space, which is required by the screw A, as shown in Fig. l. Each of the two threads A, in Fig. 3, take a halt turn,` or nearly so, around their shaft, or axis of motion.

Various modes oit gearing the propeller may be adopted, such as a gearing of cog wheels, or the employment ot metallic, oi' other, hands. The propeller may be worked by hand, or by other than steam power; and it may be made of wood, sheet-iron, or other suitable material, and with threads, or worms, set at various angles with the central line of the screw.

The length and diameter ot' the thread of the screw must, of course, be proportioned to the size ot the vessel to be propelled, and althougli other circumstances must be taken into the account besides the tonnage of the vessel to be propelled, it will serve as a general guide to state that in a vessel of two hundred and thirtyseven tons burden, and with a draft of wter ot nine feet tour inches, a screw propeller having one single turn, eight feet in length, and tive feet nine inches in diameter; or having a double thread, each making one-halt turn, of the same diameter, and tour feetin length, has been found to answer well.

Having thus fully described the nature ot my invention, and shown the manner in which the Sanne is to be carried into operation, what I claim therein as new, and desire to secure by Letters Patent, is-

The arranging, or placing, of a screw propeller, in the dead Wood, or dead rising,

of it vessel, the thread of which screw should nmke one entire revolution, or nearly so, upon its shaft; which thread may be n one Continuous piece, or it may be divided into 

